Mañihuales River at a glance
- Where
- North of Coyhaique, Aysén Region, Chilean Patagonia
- Main tributaries
- The Ñirehuao and the Emperador Guillermo
- Joins
- The Simpson, forming the Aysén River
- Type of water
- Freestone, fed by rain and snowmelt
- Fish
- Brown and rainbow trout; chinook salmon spawn in it
- Closed area
- Sector El Toqui: chinook spawning area, no fishing all year
- Flow gauge
- DGA station Río Mañihuales antes junta con Simpson (11308001-9)
Where is the Mañihuales River?
In the north of the Aysén basin, in the Aysén Region of Chilean Patagonia. Chile's water authority, the DGA, describes a river that first runs north to south and then turns west. On the way it takes in its two main tributaries, the Ñirehuao and the Emperador Guillermo, and it ends where it meets the Simpson: the two form the Aysén River.
A note for anyone searching in English: the Wikipedia article titled "Mañihuales River" describes a different river of the same name, on the Isthmus of Ofqui far to the south. This page is about the Mañihuales of the Aysén basin.
What kind of river is the Mañihuales?
A freestone fed by rain and snowmelt, like the rest of the basin. On the morning of 7 August 2026 its gauge above the Simpson junction read 77.03 m³/s, the biggest flow on our conditions page that morning (the Simpson read 20.0 m³/s), and at 7.6 °C it was also the warmest.
It carries the water of the northern basin: the steppe freestone of the Ñirehuao and the smaller Emperador Guillermo. Our hydrological guide to Coyhaique's rivers explains how the basin responds to snowmelt and rain.
What fish are in the Mañihuales?
Brown and rainbow trout, the two trout species the DGA records in the Aysén basin. In the terrestrial season, hoppers and beetles bring big trout to the surface, and on the Mañihuales that includes the cantaria beetle. Chinook salmon also spawn in the Mañihuales, which is why Sernapesca closes part of it all year.
Where fishing is closed on the Mañihuales
Sernapesca protects the Mañihuales in the El Toqui sector as a spawning area for chinook salmon, which spawn there in April and May. No fishing is allowed there at any time of year, not even catch and release. The general Aysén river periods, in the table below, apply elsewhere. Chinook have their own season in Aysén, from 12 October to 15 January. Details in our guide to Aysén fishing rules and licence.
Checking the Mañihuales before a day on the water
Its DGA gauge is one of the stations on our live river conditions. We guide out of Coyhaique, and the water for each day is chosen from flow and wind.
Aysén river rules, 2026–27 season
| Dates | Rule |
|---|---|
| 12 October – 30 November | Catch and release only |
| 1 December – 28 February | Up to 3 fish or 15 kg per angler per day |
| 1 March – 6 May | Catch and release only |
| 7 May – 11 October | Closed season |
Source: Sernapesca, management measures for recreational fishing, 2025–2027 seasons. Chinook salmon have their own season, and some spawning areas are closed all year. We guide from October 12 to April 30 and release every fish.
We guide out of Coyhaique, and the water for each day is chosen from flow and wind. See the rivers and lakes we float or the live river conditions.